FabDigitFabDigit

Steel 4626 QT-28-32HRC vs 4626 QT-38-42HRC

Steel · 4626 temper comparison

4626 QT-28-32HRC and 4626 QT-38-42HRC are two conditions of the same steel grade, 4626: QT-28-32HRC versus QT-38-42HRC. The chemistry is identical, so every difference below comes from the condition. 4626 QT-38-42HRC is the stronger of the two: yield strength 1,180 MPa (171 ksi) against 830 MPa (120 ksi) for 4626 QT-28-32HRC, about 42% more; tensile strength follows at 1,300 MPa (189 ksi) vs 960 MPa (139 ksi). In exchange, 4626 QT-28-32HRC is the more ductile: elongation 18% versus 13% for 4626 QT-38-42HRC, and 4626 QT-38-42HRC is harder (375 HB vs 285 HB). 4626 QT-28-32HRC runs hotter in service (425°C vs 300°C continuous). On the shop floor, 4626 QT-28-32HRC welds better (fair vs poor).

4626 QT-28-32HRCChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.

4626 QT-38-42HRCChoose it when strength drives the design.

4626 QT-28-32HRC vs 4626 QT-38-42HRC: properties

4626 QT-28-32HRC4626 QT-38-42HRC

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

960 MPa139 ksi
1,300 MPa189 ksi

Yield Strength (0.2% offset)

830 MPa120 ksi
1,180 MPa171 ksi

Elongation at Break

18%
13%

Reduction in Area

58%
48%

Shear Strength

620 MPa89.9 ksi
810 MPa117 ksi

Fatigue Strength (Endurance Limit)

450 MPa65.3 ksi
570 MPa82.7 ksi

Charpy V-Notch Impact (RT)

70 J51.6 ft·lbf
38 J28 ft·lbf

Hardness, Brinell

285 HB
375 HB

Hardness, Vickers

302 HV
395 HV

Same in both: Elastic (Young's) Modulus 205 GPa29.7 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Hardness, Rockwell B 82 HRB

Physical

Density and transition temperatures.

Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,425°C2,597 °F · Liquidus Temperature 1,500°C2,732 °F

Thermal

How each material carries heat and how hot it can run.

Max Service Temperature (continuous)

425°C797 °F
300°C572 °F

Same in both: Thermal Conductivity 44 W/m·K25.4 BTU/hr·ft·°F · Specific Heat Capacity 475 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.9 µm/m·K6.6 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -60°C-76 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 7.8 % IACS · Electrical Resistivity 2.2×10⁻⁷ Ω·m8.66 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.61 V · Corrosion Resistance 12 / 100

Manufacturability

FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.

Machinability Rating (AISI 1212 = 100 %)

50%
32%

Weldability

35 / 100
22 / 100

Same in both: Machinability 60 / 100 · Formability (cold) 50 / 100 · Brazeability / Solderability 60 / 100 · Polishability 65 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 32 MJ/kg13,758 BTU/lb · Embodied Carbon (primary production) 2.3 kg CO₂/kg · Embodied Water 60 L/kg7.2 gal/lb · Typical Recycled Content 25%

Strength versus weight

Yield strength against density for every steel grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.

2005001,0002,0007.588.5Density (g/cm³)Yield strength (MPa) — log scale4626

4626 QT-28-32HRC vs 4626 QT-38-42HRC — frequently asked

Is 4626 QT-38-42HRC stronger than 4626 QT-28-32HRC?

Yes. 4626 QT-38-42HRC has a typical yield strength of 1,180 MPa (171 ksi) against 830 MPa (120 ksi) for 4626 QT-28-32HRC — about 42% more. Tensile strength is 1,300 MPa (189 ksi) vs 960 MPa (139 ksi).

Which condition does FabDigit quote by default, QT-28-32HRC or QT-38-42HRC?

A is the default 4626 condition in the FabDigit quote flow (neither QT-28-32HRC nor QT-38-42HRC). The other condition is available on request or by drawing note — specify it in the material field or the part notes and the quote is priced for it.

Which welds better, 4626 QT-28-32HRC or 4626 QT-38-42HRC?

4626 QT-28-32HRC. Its weldability rates fair (35/100) against poor (22/100) for 4626 QT-38-42HRC.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 4626 QT-28-32HRC and 4626 QT-38-42HRC side by side — material, machining time, tolerance and finish in one quote. Certified material data ships with the order on request.

Typical handbook values for the conditions named above, normalised for comparison. Hardness on non-Brinell scales is converted approximately for charting only. Request certified data with your order for design-critical properties.